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United States Department of Agriculture

Agricultural Research Service

Research Project: VITAMIN K: FOOD COMPOSITION, BIOAVAILABILITY AND IT'S ROLE IN HUMAN HEALTH Title: Circulating phylloquinone concentrations of adults in the United States differs according to race/ethnicity

Authors
item Shea, M. Kyla -
item Booth, Sarah L. -
item Nettleton, Jennifer A. -
item Burke, Gregory L. -
item Chen, Haiying -
item Kritchevsky, Stephen B. -

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 10, 2012
Publication Date: May 1, 2012
Citation: Shea, M., Booth, S., Nettleton, J., Burke, G., Chen, H., Kritchevsky, S. 2012. Circulating phylloquinone concentrations of adults in the United States differs according to race/ethnicity. Journal of Nutrition. 111:154278.

Interpretive Summary: Differences in micronutrient status are reported to contribute to race/ethnic differences in chronic diseases. Diseases for which vitamin K has a role in their etiology, are reported to differ by race/ethnicity, but it is unclear if vitamin K status also differs by race/ethnically. We examined race/ethnic differences in serum vitamin K in the Multiethnic Study of Atherosclerosis (MESA). The average age of the participants was 62 years and 52% were women. The study included 262 white, 180 African American, 169 Hispanic, and 93 Chinese participants. Overall, 25% had serum vitamin K concentrations that were below the lower limit of detection of the method used for vitamin K analysis. However, the prevalence of non-detectable serum vitamin K concentrations in Chinese was significantly less than the other three race/ethnic groups studied. In contrast, the odds for African-Americans and Hispanics to have non-detectable serum vitamin K concentrations did not differ from whites. When all the detectable serum vitamin K concentrations were compared across groups, serum vitamin K was higher in the Chinese compared to whites, African Americans, and Hispanics. These findings suggest serum vitamin K differs by race/ethnicity in US adults, especially among those of Chinese descent, which merits consideration in the design and interpretation of future population-based and clinical studies of vitamin K-related diseases.

Technical Abstract: Differences in micronutrient status are reported to contribute to race/ethnic differences in chronic diseases. Diseases related to vitamin K are reported to differ by race/ethnicity, but it is unclear if circulating vitamin K concentrations also differ race/ethnically. We examined race/ethnic differences in serum phylloquinone (vitamin K1) in the Multiethnic Study of Atherosclerosis (MESA) [mean +/-SD age=62 +/-10 y; 52% female; 262 white, 180 African 6 American, 169 Hispanic, 93 Chinese]. Overall, 25% had serum K1 <0.1 nmol/L (the lower limit of detection, LLD). The prevalence of low serum K1 was 4% in Chinese, compared to 24% of whites, 29% of African Americans, 33% of Hispanics. Compared to whites, Chinese were significantly less likely to have serum K1 < LLD [odds ratio (95%CI) 0.23(0.09-0.23), adjusted 10 for triglycerides, K1 intake, age, gender, BMI, smoking, total cholesterol, site, season, lipid-11 lowering medication use). African-Americans and Hispanics had similar odds to whites for having serum K1 <LLD [OR(95%CI) = 1.30(0.79-2.15) and 1.19(0.66-2.15) respectively, fully adjusted]. In participants with detectable levels (n=523), (natural log) serum K1 was higher in the Chinese compared to whites, African Americans, and Hispanics [geometric mean +/-SEM = 15 2.2+/-0.1 nmol/L vs. 1.2+/-0.1 nmol/L, 1.5+/-0.1 nmol/L, and 1.1+/-0.1 nmol/L respectively, adjusted for triglycerides, K1 intake and additional covariates; all p<0.001]. These findings suggest circulating K1 differs by race/ethnicity in US adults, especially among those of Chinese descent, which merits consideration in the design and interpretation of future population-based and clinical studies of vitamin K and related diseases.

Last Modified: 12/22/2014